It's not just nostalgia glasses. The old Mario cartoons really captured the feel of the games. All of Mario's power-ups were there, the green pipes, even sound effects from the games.
None of Sonic's cartoons were able to do that.
SatAM was full of original characters & furry drama bullshit
Underground had that dumb rock-band angle, and added some Hedgehog Queen.
Sonic X focused more on the new human characters & had an awful dub.
AoSTH looked like garbage, & introduced that dumb chili dog thing, but at least it was funny. Still lacked the feel of the games, though.
Another thing Mario has over Sonic is that the Mario games aren't filled up the wazoo with game-breaking bugs and terrible physics.
Yeah, Sonic2006 was awful, but still, I've had way more fun playing games like SA1, SA2, Unleashed, Generations, SEGA Tennis, the first Sonic Riders & Advance series,
than I ever did with Mario Sunshine, Paper Mario, Mario Party, Smash Bros, MK: Double Dash! Luigi's Mansion, or any other retarded Mario spinoff.
Don't get me wrong, I loved the classic NES & SNES Mario's, but I haven't really been impressed by a Mario game since Mario 64..
IMO, Mario jumped the shark years ago..